Role Description & Responsibilities
Machine Learning
About Reddit
Reddit is a high-growth technology leader building scalable solutions for global users. Millions of companies and teams rely on their infrastructure and services to execute high-value workflows, analyze massive datasets, and scale modern operations.
CadetX Candidate Advantage: As an applicant for this Machine Learning role, you are evaluated on practical proficiency with real-world query execution, data pipelines, and clear stakeholder communication.
CadetX Role Brief & Company Specifications
Role Mission & Impact
At Reddit, machine learning sits at the heart of how millions of people discover, connect, and engage with the world’s largest collection of human conversations. From powering personalized recommendations and search to optimizing advertising systems and marketplace dynamics, our ML engineers tackle some of the most interesting and impactful problems in large-scale applied machine learning.
We hire Machine Learning Engineers across both our Consumer and Ads organizations, giving you the opportunity to work on a wide range of high-impact problems across the Reddit ecosystem.
Key Responsibilities & Day-to-Day Scope
- ✓ Personalized recommendations, search, and ranking systems that help users discover the most relevant content and communities
- ✓ Intelligent advertising systems including ranking, bidding, measurement, and optimization
- ✓ Content, Advertisers, and User understanding, from building foundational content/user representations to deriving insightful signals
- ✓ Large-scale machine learning pipelines, model serving infrastructure, and real-time decision systems
- ✓ Applied AI and LLM-driven experiences that improve relevance, discovery, and user engagement
- ✓ Design, build, and deploy production-grade machine learning models and systems at scale
- ✓ Own the full ML lifecycle: from problem definition and feature engineering to training, evaluation, deployment, and monitoring
- ✓ Build scalable data and model pipelines with strong reliability, observability, and automated retraining
- ✓ Work with large-scale datasets to improve ranking, recommendations, search relevance, prediction, content/user understanding, and optimization systems.
- ✓ Partner cross-functionally with Product, Data Science, Infrastructure, and Engineering teams to translate complex problems into ML solutions
- ✓ Improve system performance across latency, throughput, and model quality metrics
- ✓ Research and apply state-of-the-art machine learning and AI techniques, including deep learning, graph & transformers based, and LLM evaluation/alignment
- ✓ Contribute to technical strategy, architecture, and long-term ML roadmap
- ✓ 3-5+ years of experience building, deploying, and operating machine learning systems in production
- ✓ Strong programming skills in Python, Java, Go, or similar languages, with solid software engineering fundamentals
- ✓ ML Fundamentals: a strong grasp of algorithms, from classic statistical learning (XGBoost, Random Forests, regressions) to DL architectures (Transformers, CNNs, GNNs)
- ✓ Hands-on experience with modern ML frameworks (e.g., PyTorch, TensorFlow)
- ✓ Experience designing scalable ML pipelines, data processing systems, and model serving infrastructure
- ✓ Ability to work cross-functionally and translate ambiguous product or business problems into technical solutions
- ✓ Experience improving measurable metrics through applied machine learning
- ✓ Experience with recommender systems, search/ranking systems, advertising/auction systems, large-scale representation learning, or multimodal embedding systems
- ✓ Familiarity with distributed systems and large-scale data processing (Spark, Kafka, Ray, Airflow, BigQuery, Redis, etc.)
Official Qualifications & Technical Requirements
- • Experience working with real-time systems and low-latency production environments
- • Background in feature engineering, model optimization, and production monitoring
- • Experience with LLM/Gen AI techniques, including but not limited to LLM evaluation, alignment, fine-tuning, knowledge distillation, RAG/agentic systems and productionizing LLM-powered products at scale
- • Advanced degree in Computer Science, Machine Learning, or related quantitative field
- • Ads Measurement Modeling
- • Ads Targeting and Retrieval
- • Advertiser Optimization
- • Ads Marketplace Quality
- • Ads Creative Effectiveness
- • Ads Foundational Representations
- • Ads Content Understanding
- • Search and Answers Relevance
- • ML Understanding
- • Notifications Relevance
- • Comprehensive Healthcare Benefits and Income Replacement Programs
- • 401k with Employer Match
- • Global Benefit programs that fit your lifestyle, from workspace to professional development to caregiving support
- • Family Planning Support
- • Gender-Affirming Care
- • Mental Health & Coaching Benefits
- • Flexible Vacation & Paid Volunteer Time Off
- • Generous Paid Parental Leave
Preferred Skills & Technology Stack
- + Familiarity with MLOps pipelines (Docker, Kubernetes, Kubeflow, Triton Inference Server).
- + Knowledge of distributed training techniques and GPU acceleration (CUDA).
- + Relevant coursework, research publication, or open-source contribution in ML/DL.
Tech Stack & Tools in this role
Expected technical competencies for Day 1 productivity:
★ Life & Culture at Reddit
Verified EmployerReddit champions rigorous analytical discipline, continuous learning, and low-ego teamwork. Team members enjoy flexible hybrid allowances, learning stipends, and structured mentorship to fast-track career mobility.